chore: checkpoint web Blender migration source, tools and docs

Accumulated uncommitted work: GHOST Web backend, WebGL/GPU web layer,
web workflow engine and protocol, tooling, docs and task records.
Large generated evidence, user-testing archives, build snapshots and
imported test assets remain untracked.

Co-Authored-By: Claude Code <noreply@anthropic.com>

web/tests/fixtures/node-graph-main-snapshots.py

@@ -0,0 +1,19 @@
+import bpy
+import json
+import pathlib
+import sys
+
+arguments = sys.argv[sys.argv.index("--") + 1:]
+destination = pathlib.Path(arguments[0])
+tree = bpy.data.node_groups[arguments[1] if len(arguments) > 1 else "Web Authored Geometry"]
+transform = next((node for node in tree.nodes if node.bl_idname == "GeometryNodeTransform"), None)
+destination.write_text(json.dumps({
+    "name": tree.name,
+    "treeCount": len(bpy.data.node_groups),
+    "nodes": sorted(node.bl_idname for node in tree.nodes),
+    "links": len(tree.links),
+    "interfaceSockets": len([item for item in tree.interface.items_tree if item.item_type == "SOCKET"]),
+    "translation": list(transform.inputs["Translation"].default_value) if transform else None,
+    "owners": sorted(obj.name for obj in bpy.data.objects if any(
+        modifier.type == "NODES" and modifier.node_group == tree for modifier in obj.modifiers)),
+}, indent=2) + "\n")